Under President Trump’s plan, the United States would govern Gaza and expel its residents. Under the Arab plan, Gaza would be run by Palestinian technocrats within a wider Palestinian state. By one Israeli proposal, Israel would cede some control to Palestinians but block Palestinian statehood. By another, Israel would occupy the entire territory.

Since the opening weeks of the war in Gaza, politicians, diplomats and analysts have made scores of proposals for how it might end, and who should subsequently govern the territory. Those proposals grew in number and relevance after the sealing of a cease-fire in January, increasing the need for clear postwar plans. And when Mr. Trump proposed to forcibly transfer the population later that month, it fueled a push across the Middle East to find an alternative.

The problem? Each plan contains something unacceptable to either Israel or Hamas, or to the Arab countries like Egypt and Saudi Arabia who some hope will fund and partially oversee Gaza’s future.

“The devil is in the details, and none of the details in these plans make any sense,” said Thomas R. Nides, a former United States ambassador to Israel. “Israel and Hamas have fundamentally opposed positions, while parts of the Arab plan are unacceptable to Israel, and vice versa. I’m all for people suggesting new ideas, but it is very hard for anyone to find common ground unless the dynamics change significantly.”

The central challenge is that Israel wants a Hamas-free Gaza whereas the group still seeks to retain its military wing, which led the October 2023 attack on Israel that ignited the war.